Common causes

Likely causes of vaginal bleeding depend on the woman’s age.

Newborn girls may have a small amount of vaginal bleeding. Before birth, they absorb estrogen through the placenta from their mother. After birth, these high levels of estrogendecrease rapidly, sometimes causing a little bleeding during the first 1 to 2 weeks of life.

During childhood, vaginal bleeding is abnormal and uncommon. When it occurs, it is most often caused by

A foreign object (body), such as toilet paper or a toy, in the vagina or an injury

Anovulatory means that the ovaries do not release an egg (ovulate), as normally occurs during a menstrual cycle. Anovulatory uterine bleeding results from changes in the hormonal control of the menstrual cycle. It is more likely to occur in adolescents (when menstrual periods are just starting) or in women in their late 40s (when periods are nearing an end).

Other common causes of vaginal bleeding during the childbearing years include

Complications of pregnancy in a woman who does not know she is pregnant

Less common causes

Certain hormonal disorders (such as hypothyroidism) are a less common cause of bleeding. Excessively heavy menstrual periods may be the first sign of a bleeding disorder.

Children may have hormonal abnormalities that cause puberty to begin too early—a disorder called precocious puberty. In these children, menstrual periods start, breasts develop, and pubic and underarm hair appears too soon. Rarely, bleeding is caused by a tumor or an injury resulting from unsuspected child abuse.

Evaluation

Doctors first focus on determining whether the cause is a serious disorder (such as an ectopic pregnancy) and whether the bleeding is excessive, possibly resulting in shock.

Doctors check for pregnancy in all women of childbearing age.

Warning signs

In women with vaginal bleeding, certain characteristics are cause for concern:

Bleeding that occurs before menstrual periods start (before puberty) or after they stop (after menopause)

Bleeding during pregnancy

Excessive bleeding

In children, difficulty walking or sitting, bruises or tears around the genitals or anus or mouth, and /or vaginal discharge or itching (which may be signs of sexual abuse)

Bleeding is considered excessive if any of the following occur:

Women lose more than about a cup of blood.

More than 1 pad or tampon is saturated per hour for a few hours.

The blood contains large clots.

When to see a doctor

Women with most warning signs should see a doctor immediately, as should those with large clots or clumps of tissue in the blood or with symptoms suggesting a bleeding disorder. These symptoms include easy bruising, excessive bleeding during toothbrushing or after minor cuts, and rashes of tiny reddish purple dots or larger splotches (indicating bleeding in the skin). However, if the only warning sign is vaginal bleeding before puberty or after menopause, a delay of a week or so is not harmful.

Women without warning signs should schedule a visit when practical, but a delay of several days is not likely to be harmful.

If vaginal bleeding continues in newborns for more than 2 weeks, they should be seen by a doctor.

What the doctor does

Doctors first ask the woman questions about her symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination often suggests a cause of the bleeding and the tests that may need to be done (see Table: Some Causes and Features of Vaginal Bleeding ).

Doctors ask about the bleeding:

How many pads are used per day or hour

How long bleeding lasts

When it started

When it occurs in relation to menstrual periods and sexual intercourse

They also ask about the woman's menstrual history:

How old she was when menstrual periods started

How long they last

How heavy they are

How long the interval between periods is

Whether they are regular

The woman is asked whether she has had previous episodes of abnormal bleeding, has had a disorder that can cause bleeding (such as a recent miscarriage), or takes birth control pills or other hormones.

The woman is asked about other symptoms, such as light-headedness, abdominal pain, and excessive bleeding after toothbrushing or a minor cut.

The physical examination includes a pelvic examination. During the examination, doctors can identify precocious puberty in children (based on the presence of pubic hair and breasts) and can sometimes identify disorders of the cervix, uterus, or vagina.

Some Causes and Features of Vaginal Bleeding

Cause

Common Features*

Tests

During infancy

Exposure to the mother's estrogen before birth

A small amount of bleeding during the first 1–2 weeks of life

A doctor's examination

During childhood

A foreign object (body) in the vagina

Usually a foul-smelling discharge, often containing small amounts of blood

Sometimes a history of having inserted an object into the vagina

A doctor's examination, sometimes done after the girl is sedated or given a general anesthetic

Blood tests to assess the blood’s ability to clot (prothrombin time and partial thromboplastin time)

Examination of a sample of blood under a microscope

Injury (including that resulting from sexual abuse)

Sometimes a history of injuries

Often vaginal discharge

A doctor's examination

If sexual abuse is suspected:

Examination under a microscope and analysis of a sample of the discharge

Tests to detect sexually transmitted diseases using a sample of secretions taken from the cervix

*Features include symptoms and results of the doctor's examination. Features mentioned are typical but not always present.

†In anovulatory uterine bleeding, the ovaries do not release an egg (ovulate). This type of bleeding results from changes in the hormonal control of the menstrual cycle.

CT = computed tomography; MRI = magnetic resonance imaging.

Testing

If women are of childbearing age, doctors always do

A urine test for pregnancy

If the urine pregnancy test is negative but doctors still suspect pregnancy, a blood test for pregnancy is done. The blood test is more accurate than the urine test when a pregnancy is very early (less than 5 weeks).

Tests commonly done include blood tests to measure thyroid hormone levels and, if bleeding has been heavy or lasted a long time, a complete blood cell count to check for anemia. Other blood tests are done depending on the disorder doctors suspect. For example, if a bleeding disorder is suspected, the blood's ability to clot is assessed. If polycystic ovary syndrome is suspected, blood tests to measure male hormone levels are done.

Ultrasonography is often used to look for abnormalities in the reproductive organs, particularly if women are over 35, if they have risk factors for endometrial cancer, or if bleeding continues despite treatment. For ultrasonography, a handheld ultrasound device is usually inserted into the vagina, but it may be placed on the abdomen.

If ultrasonography detects thickening of the uterine lining (endometrial hyperplasia), hysteroscopy or sonohysterography may be done to look for small growths in the uterus. For hysteroscopy, a viewing tube is inserted into the uterus through the vagina. For sonohysterography, fluid is infused into the uterus during ultrasonography to make abnormalities easier to identity. If results of these tests are abnormal or if they are inconclusive in women over 35 or with risk factors for cancer, doctors may take a sample of tissue from the lining of the uterus for analysis. The sample may be obtained by suction (through a tube) or by scraping—a procedure called dilation and curettage (D and C).

Other tests may be done, depending on which disorders seem possible. For example, a biopsy of the cervix may be done to check for cancer of the cervix.

If abnormal bleeding does not result from any of the usual causes, it may be related to changes in the hormonal control of the menstrual cycle.

Treatment

If women are in shock, they are given fluids intravenously and blood transfusions as needed to restore blood pressure.

When vaginal bleeding results from another disorder, that disorder is treated if possible. If bleeding has caused iron deficiency, women are given iron supplements.

Polyps, fibroids, cancers, and some benign tumors may be surgically removed from the uterus.

Essentials for Older Women

Postmenopausal bleeding (occurring more than 6 months after menopause) is considered abnormal, even though it is relatively common. Such bleeding can indicate a precancerous disorder (such as thickening of the lining of the uterus) or cancer. Thus, if such bleeding occurs, older women should see a doctor promptly so that cancer can be ruled out.

Older women should also see a doctor promptly if they have

Any vaginal bleeding

A discharge that is pink or brown, possibly containing small amounts of blood

However, postmenopausal bleeding has many other causes. They include

Thinning and drying of the lining of the uterus or vagina (the most common cause)

Use of estrogen or other hormone therapy, particularly when use is stopped

Polyps in the cervix or uterus

Fibroids

Infections

Because the tissues of the vagina may be thin and dry, examination of the vagina may be uncomfortable. Doctors may try using a smaller instrument (speculum) to make the examination less uncomfortable.

Key Points

During the childbearing years, the most common cause of abnormal vaginal bleeding is pregnancy.

In women who are not pregnant, the most common cause is anovulatory uterine bleeding, which is related to changes in the hormonal control of the menstrual cycle that prevent the ovaries from releasing an egg.

In children, the cause is usually a foreign object or an injury, but sometimes sexual abuse is the cause.

In women of childbearing age, a pregnancy test is done even when women do not think they could be pregnant.

If any vaginal bleeding occurs after menopause, an evaluation to rule out cancer is necessary.

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